Witch Hazel Gall Aphid on Fothergilla: Identifying Those Cone-Like Growths

Those strange cone-like shapes on your fothergilla leaves are caused by witch hazel gall aphid. Fothergilla (witch elder) belongs to the same family as witch hazel (Hamamelis) and winter hazel (Corylopsis), all of which host this tiny insect. The aphid induces leaf tissue to swell into a protective cone around her body.

Baby aphids develop inside the gall until late summer, when they emerge to lay eggs on nearby shrubs. The good news: these galls don't harm the host plant. No treatment is needed—just appreciate this fascinating plant-insect interaction.